Internal-combustion engine and crank shaft therefor



P. A. LEBEDA May 29, 1951 INTERNAL-COMBUSTION ENG INE AND CRANK SHAFTTHEREFOR '2 Sheets-Sheet 1 Filed Jan. 9, 1948 FIG IN VEN TOR.

P. A. LEBEDA BY I ATTORNEY INTERNAL-COMBUSTION ENGINE AND CRANK SHAFTTHEREFOR 7 Filed Jan. 9, 1948 P. A. LEBEDA May 29, 1951 2 sheets-sheet 28 M 1 I V a 3 LJ M u INVEN TOR.

P. A. LEBEDA ATTORNEY Patented May 29,

INTERNAL-COMBUSTION ENGINE AND CRANK SHAFT THEREFOR Paul A. Lebeda,Cedar Rapids, Iowa Application January 9, 1948, Serial No. 1,466

@Mypresent invention relates to internal combustion engines and moreparticularly, although 'not exclusively, to an improved crank shaft forfurther objects, advantages and capabilities as will hereafter appearand as are inherent in the construction disclosed herein. My inventionfurtherresides in the combination, construction, and

arrangement of parts illustrated in the accompanying drawings and, whileI have shown therein what is now regarded as the preferred embodiment-ofthisinvention, I desire the sameto be understood as illustrative onlyand not to be interpreted in a limiting sense.

: Inthe drawings annexed hereto and forming a part hereof,

Fig. 1 is a side elevation of a crank shaft in accordance with mypresent invention; V

Fig. 2 is an end elevation looking at the left hand end of the structureas shown in Fig. l; Fig. 3 represents a transverse section takensubstantially along the plane indicated by the line 3-3, Fig. 1; l Fig.4 represents a transverse section taken substantially along the planeindicated by the line 4 4, Fig. 1;

Fig. 5is an end elevation of the structure shown inFig. 1, looking atthe right hand end thereof; Fig. 6 represents a transverse section takensubstantially along the plane indicated by the line, 6-45, 'Fig. l; f

Fig. 7 is an elevational view, comparable to Fig.1, of an incompletecrank shaft;

Fig. 81s a perspective view of one of the blocks used in connection withthe structure shown in Fig. 7 to build up the structure shown in Fig. 1;

. Fig. 9 represents a central longitudinal section of an engine inaccordance with my invention; Fig. 10 is a detail view of the forwardend of the propeller shaft, in section;

1 Fig. 11 shows a horizontal section of one of the cylinders, with thepiston shown in plan view, the

5 Claims. (Cl. 12373) 2 section being taken substantially along theplane indicated by the line I ll I, Fig. 9; and

Fig. 12 represents a longitudinal section through one of the cylinders,substantially along the plane indicated by the broken line l2-l2, Fig.11.

.Reference will now be made in greater detail to the annexed drawingsfor a more complete description of this invention. The shaft propercomprises two sections l and 2 which are hollow for the greater portionof their length. These sections I and 2 are connected by crank pins 3and 4 and supporting plates 5, 6, l, and 8. The plates 6 and l,surrounded by a cylindrical member l0, together with the blocks II andI2, constitute a valve 9 for controlling the flow of fuel to thecylinders. Contained within the cylindrical member Ill are the twoblocks l l and I2 which are provided with cavities I3 and [4 which serveas the receiving chambers for charges of carbureted fuel to be deliveredto the cylinders.

It will be seen from Figs. 1 and 2 that there are flattened areas I5 andIE on the crank shaft section I. These fiat areas serve as timing meansfor controlling the firing of the engine, as will be understood by thosefamiliar with the art of internal combustion engines. A fiat spacer orspacing plate I! integrally joins the plates 6 and 'l and separates thespace between them into two chambers in which the blocks II and I2 arereceived. A resilient, rubber-like material I8 is placed between theblocks II and i2 and the spacer plate I1 and is compressed slightly topermit the cylindrical member or sleeve 10 to be put in place.Corresponding to the cavities l3 and M are openings I9 and 2B in thesleeve I0 which permit the explosive charges of mixed fuel and air toenter the cavities l3 and I4. An opening 2| through the plate 6 and acorresponding opening 22 through the plate I serve as means to permitthe carbureted fuel to pass from the chambers I3 and [4 into the spaces23 and 24 in which the connecting rods25 move. It is from these chambersthat the fuel passes up into the cylinders 26 and 27 where it iscompressed by the pistons and fired.

The pistons 28 and 29 are recessed along their upper edges to give thecarbureted mixture increased access to the cylinders. This is shownclearly in Figs. 9, 11, and 12. As is clear from between posts 32 and33.

Figs. 9 and 11, the cylinders are thin walled and the walls are providedwith openings 38 and 3| The openings 3| are covered by a bridge 34 whichencloses a channel 35 adapted to convey the carbureted air-gas mixturefrom the crank shaft chambers to the cylinders 26 and 21.

When the piston is in its lowermost position, the recess 35 in the upperedge of the piston is opposite the openings 3| and free ingress istherefore provided for the mixture entering the cylinder chamber 26 or2?. Then, when the piston moves upwardly, it closes the openings 3|,acting as a valve to trap the charge of air-gas mixture in the cylinder.The recess 31, at the opposite side of the piston from the recess 36,serves to permit the burned gas to escape from the cylinder, the gasescaping through the openings 30. This happens at the same time as theinlet of gas through the openings 3 I.

The lateral walls and heads of the cylinders are provided with a numberof heat-radiating fins for rapid heat dissipation. The cylinders arealso provided with flanges 38 by means of which flanges the cylindersare secured to the engine block 39 in which the crank case is located.

It is seen from Fig. 9 that the valve 9, comprising the parts (5, i,ll], H, and I2, serves as a separator between the two sections of thecrank case. An enlargement, in the form of an elongated lug, is formedon the lower part of the block and this is provided with a longitudinalslot 4| into which the carbureted mixture is delivered from the venturiin the opening 40, which opens into the slot 3| extending around thecrank case about ninety degrees (90). The carburetor is described indetail in another application filed contemporaneously herewith. Theopening 42 is the air-admission opening for the carburetor, through thewall of which and the venturi is formed an opening for the reception ofthe needle valve, shown in the application mentioned above.

In order to make the propeller readily detachable, in event such bedesirable, I secure an aluminum plate 43 to the propeller 45 and thenpass a bolt l i through the propeller and plate and into the shaft 2.The plate 43 is made with a key 46 which engages in notche cut into theend of the hollow shaft 2, as shown in Fig. 1. This key fits in thenotches in the end of the shaft and is held tightly assembled withrelation thereto by the screw or bolt 44.

It is of course understood that the specific description of structureset forth above may be departed from without departing from the spiritof this invention as disclosed in this specification and as defined inthe appended claims.

Having now described my invention, I claim:

1. A crank shaft for an internal combustion engine comprising a pair ofaligned shaft sections, at coaxially arranged circular plate attached tothe inner end of each shaft section, a crank pin extending inwardly fromeach plate toward the other but arranged in diametrical relation withreference to the plates, other circular plates attached to the innerends of said crank pins and in coaxial relation with reference to thefirst plates, and a spacer plate connecting the inner plates, holdingthem in axial alignment and dividing the space between said inner platesinto two substantially equal and identical spaces.

2. A motor comprising an engine block having cylinder members mountedthereon, said members having downward extensions fitting into similarlyshaped openings in the block, said extensions each being provided with alaterally extending flange by means of which it may be attached to theblock, a piston reciprocating in each extension and cylinder, aconnecting rod extending from each piston into the block, a crank shaftextending longitudinally of the block, said crank shaft having a crankpin for each connecting rod to which the rods are respectivelyconnected, said block having a transversely extending boss locatedsubstantially midway between the cylinders, said boss having a slotextending lengthwise thereof transversely of the block and communicatinginwardly with the opening in the block in which the crank shaft islocated, a boss on the block having an opening extending therethroughand opening into said slot, a fluid fuel valve extending through a wallof the second boss' and terminating near the axis of the opening throughthe second boss, and a rotary valve member having compartments receivingfuel from said slot and delivering same to the cylinders.

3. A crank shaft for an internal combustion engine comprising a pair ofaligned shaft sections, a coaxially arranged circular plate attached tothe inner end of each shaft section, a crank pin extending inwardly fromeach plate toward the other but arranged in diametrical relation withreference to the plates, other circular plates attached to the innerends of said crank pins and in coaxial relation with reference to thefirst plates, a spacer plate connecting the inner plates, holding themin axial alignment and dividing the space between said inner plates intotwo substantially equal and identical spaces, blocks fitted into and"secured in said spaces, each of said blocks having a compartment in anedge thereof located away from said spacer plate, and a cylindricalsleeve peripherally surrounding said blocks and said other circularplates and secured in place thereon, said sleeve having aperturesthrough the cylindrical wall thereof in alignment with the compartmentsin the blocks, each of the intermediate plates having an opening inalignment with one of the compartments, whereby to. admit carbureted gasfrom the engine crank case into said. compartments.

4. In an internal combustion motor, a crank shaft having fourtransversely extending plates of substantially cylindrical form, theouter plates and the next inner plates being connected by crank pinsarranged at opposite sides of the axis of the shaft, the innerplatesbeing connected by a spacer plate axially arranged with relationto the plates, blocks arranged on opposite sides of the spacer platebetween the inner two of the four transverse plates, each block havingon its face remote from the spacer plate a channel serving as achargefeeding device for feeding charges ofcarbureted mixture to themotor cylinders, and a cylindrical sleeve surrounding said inner plates,said sleeve having two openings through its cylindrical surfaceconnecting with the respective channels in the blocks.

5. A crank shaft for an internal combustion motor comprising spacedcoaxial sections of a shaft, a plurality of cylindrical platesv incoaxial relationship with the shaft sections and arranged between them,the outer plates being connected integrally with the inner ends or theshaft sections, the inner plates being integrally connected by crankpins to the inner faces of the outer plates and to each other by aspacing plate, said spacing plate dividing the space between the innerplates into two substantially equal compartments, and blocks locatedinj'said compartments, said blocks having peripheral cavities, saidblocks and inner plates being surrounded by a closely fitting sleeveprovided with apertures registering with the cavities in the blocks.

PAUL A. LEBEDA.

REFERENCES CITED The following references are of record in the file ofthis patent:

Number Number Great Britain of 1923

